Rare 'thundersnow' storm hits Montreal

A rare weather event known as "thundersnow" was captured on Feb. 29 in Montreal.

Combining a unique mix of snow, lightning and thunder, the snow shower came just before a major storm hit the city.

Thundersnow events are rare: less than 1 percent of all snowstorms are associated with thunder, according to ABC News. They require just the right mix of atmospheric instability and upward motion of warm air that make both snowstorms and thunder unique.

Thundersnow has also proved helpful for meteorologists predicting future storms. "Thunder and lightning existing in the storm are usually a symptom of something else," Patrick Market, associate professor of atmosphere science at the University of Missouri, told ABC News. "That's usually a harbinger of somebody getting a significant snowfall later on."